Reversing spray head assembly for automatic dishwasher



A. L. HARDY June 3, 1969 REVERSING SPRAY HEAD ASSEMBLY FOR AUTOMATICDISHWASHER Filed Aug. 11, 1967 Sheet o E 1/ f.

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INVENTOR. ALBERT L. HARDY BY IZE- ms ATTQRNEY June 3, 1969 A. L. HARDY3,447,752

REVERSING SPRAY HEAD ASSEMBLY FOR AUTOMATIC DISHWASHER Filed Aug. 1l.1967 Sheet Of 2 48a. {37 l`\\ Z f 4\ B. r 46 35 INVENTOR.

53 so 52 ALBERT HARDY sus ATTORNEY United States Patent U.S. Cl. 239-251lClaims ABSTRACT OF THE DISCLOSURE A reversing spray head assembly foran automatic dishwasher comprising a hollow casing supported in thedishwasher wash chamber for rotation about an axis transverse to thecasing major plane. Pressurized liquid is admitted to the casing throughan opening adjacent the axis of rotation and is issued into the washchamber from orifices provided in the casing. The liquid issued fromcertain of the orifices generates a washing action. A passageway isformed in an arm of the casing which extends outwardly from the axis,and the liquid conducted through it issues into the wash chamber fromeither of a pair of jet propelling orifies which open in oppositedirections from the arm. Issuance of the liquid from one of thepropelling orifices urges rotation of the casing in one direction aboutthe axis, while issuance of liquid from the other urges reverse rotationof the casing. The arm passageway is divided into an inlet portionconnected to the casing liquid inlet opening and two outlet portionswhich have a common intersection with the passageway inlet portion andextend from opposite sides thereof to a respective one of the propellingorifices. A pair of air inlet ports are provided in the casing arm andare connected by separate conduits to the opposite sides of thepassageway inlet portion adjacent the intersection. The air conduitshave a considerably smaller cross-section than the liquid passagewayportions. Control means including a cam-actuated valve plate rotatablymounted on the casing arm are provided for selectively opening andclosing the air inlet ports to allow aspiration of air through only oneof the ports at one time and thus direct the liquid toward one of thepropelling orifices and away from the other whereby direction ofrotation of the casing about the axis can be reversed.

Background of the invention This invention relates to automaticdishwashers. More particularly it relates to a reversing spray headassembly for an automatic dishwasher.

Many automatic dishwashers have a spray head assenibly comprising ahollow casing supported for rotation about an axis transverse to itsmajor plane. A plurality of orifices are provided in the casing and washfluid fed into the casing under pressure by a pump issues from certainof the orifices to generate a vigorous spray action. Others of theorifices are located at the outer ends of a pair of arms that extendoutwardly in opposite directions from the axis of rotation and areemployed as jet propelling orifices to rotate the casing about the axis.A typical dishwasher spray head assembly of this type is illustrated inU.S. Patent No. 3,288,372, issued Nov. 29, 1966, to Donald S. Cushing,and assigned to the General Electric Company, assignee of the presentinvention. In such presently known assemblies, the jet propellingorifices provide for rotation of the casing in only one direction. Whilethis unidirectional rotation of the spray head casing helps todistribute the spray about the dishwasher wash charnber, it is possiblebecause the rotation is unidirectional to miss certain portions of thesoiled articles contained within the wash chamber. Hence, it would bedesirable to periodically reverse the rotation of the spray head casing3,447,752 IPatented June 3, 1969 in order to more thoroughly distributethe spray to the soiled articles.

Summary of the invention The present invention provides a reversingspray head assembly for an automatic dishwasher, comprising: a hollowcasing supported in the dishwasher wash chamber for rotation about anaxis and having an arm extending outwardly from said axis; an opening insaid casing for admitting liquid under pressure to the inner end of saidarm; a liquid passageway in said arm for conducting liquid outwardly toa pair of orifices which open in opposite directions from said armgenerally in a plane transverse to the axis of rotation, said passagewayincluding an inlet portion connected to said opening and two outletportions having a common intersection with the inlet portion andextending outwardly from opposite sides thereof to a respective one ofthe orifices; a pair of control fluid inlet ports in said arm connectedto the opposite sides of the passageway inlet portion adjacent theintersection by separate conduits which have a considerably smallercross-section than the passageway portions; and means for selectivelyopening or closing the control fluid inlet ports to allow entry ofcontrol fluid through only one of the ports at one time and thus directthe liquid toward one and away from the other of said orifices wherebythe direction of rotation of the casing about said axis can be reversed.Preferably, the control fluid is aspirated air and the casing isprovided with at least one additional orifice for issuing the liquid togenerate a washing action within the wash chamber.

Brief description of the drawings The present invention is illustratedin the accompanying drawings, wherein:

FIGURE 1 is an elevational view, partly cut away to show details, of anautomatic dishwasher employing the present invention;

FIGURE 2 is a fragmentary partly broken top plan view of the portion ofthe spray head of the present invention which appears at the lower leftof FIGURE 1;

FIGURE 3 is a fragmentary bottom plan view of the spray head portion ofFIGURE 2, showing the air inlet valve plate in a first condition;

FIGURE 4 is a view similar to FIGURE 3 but showing the valve plate inanother condition; and

FIGURE 5 is a section taken substantially alongline 5 5 of FIGURE 2.

Description of the preferred embodiment Referring now to the drawingsand particularlyto FIGURE 1 thereof, there is illustrated an automaticdishwasher 10 having an outer cabinet 11 defining therein a wash chamber12. Disposed within the wash chamber 12 are dish-supporting racks 13 and14 which are adapted to receive and support dishes or other articlestobe washed within the wash chamber 12. A closure member or door 15 isprovided in one wall of the cabinet 11', pivotal about a hinge means 16to provide access to the wash chamber 12. When the door is pivoteddownwardly, the rack 13 can be at least partially withdrawn from thewash chamber 12. The rack 13 is mounted by means of a slide and rollersystem 17 provided at each side of the rack 13 and slidably supportingthe rack 13 from the inner wall of the cabinet 11. Similarly, the rack14 can be at least partially withdrawn from the wash chamber 12 by meansof a roller 18, which rides upon a surface '19 provided at each side ofthe cabinet 11. y

The lower extremity of the wash chamber 12 is detined by a bottom wall20 which gradually slopes to a low point 21 near the center of thedishwasher. Disposed ybelow the low point 21 is a sump 22 which may beformed integrally with the bottom wall or which may be a separateelement secured to the bottom wall 20. Disposed below and supported bythe bottom wall 20 is a motorpump assembly 23 which includes an electricmotor 24, pump 25 and an electrically-operated valve 26 (shown inblock). The sump 22 and the inlet of the pump 25 are interconnected by alarge diameter conduit 27. The conduit 27 is secured to the sump 22 bymeans of a clamp 28 and to the housing of the pump 25 by means of aclamp 29. The pump 25 has a main outlet communicating with a conduit 30which in turn communicates with a spray head 31 which is rotatablymounted atop a centrally-bored pedestal 32 formed in the bottom wall 20.

The pump 25 is also provided with an efuent discharge outlet 33 which iscontrolled by the valve 26 and is connected to the household sewersystem by suitable conduit means (not shown). The valve 26 includes anelement (not shown) within the housing of a pump 25 that is movablebetween two positions. In one of these positions the element closes theeffluent discharge outlet 33 and opens the main outlet and, in the otherof these positions, closes the main outlet and opens the efuentdischarge outlet. An electrical resistance heating element (not shown)may be provided in the lower portion of the wash chamber 12 tofacilitate drying of articles supported by the racks 13 and 14 uponcompletion of the normal wash and rinse operations.

An electrically-operated lill valve (not shown) is provided to admitwater to the wash chamber 12 and electrical sequence control means (notshown) of a wellknown type are provided for sequentially operating thepump valve 26 and the till valve.

It should, of course, be understood that all of the structure thus fardescribed may be modified a great deal without seriously affecting thepresent invention since this structure is substantially conventional andcomprises only one illustrative structure with which the presentinvention is compatible.

As discussed above, the present inven-tion is primarily concerned withproviding a reversing spray head assembly which will permit periodicreversal of the direction of rotation of a dishwasher spray head, suchas spray head 31, -about its axis of rotation, such as the pedestal 32.

In accordance with a presently preferred embodiment of the presentinvention, this is accomplished by making the spray head 31 in the formof a hollow elongate casing 34 having a liquid inlet opening 35 adjacentits bottom center which is rotatably mounted atop the pedestal 32 in ahuid-sealing relationship and a pair of arms 36 and 37 extending inopposite directions from the inlet opening 35. During the washing andrinsing operations, wash fluid from the sump 22 is propelled underpressure into the opening 35 of the hollow casing 34 by the motorpumpassembly 23 through the conduit 30 and is conducted outwardly throughthe hollow casing arms 36 and 37. At least one of the casing arms 36(the right as seen in the drawings) is provided with at least oneorifice 38 in its upper surface through which the pressurized wash fluidis issued upwardly to generate a wash action within the wash chamber 12.

As best shown in FIGURE 2, the other hollow casing arm 37 (the left asseen in the drawings) is provided adjacent its outer end with a pair ofjet propelling orifices 39 and 40 which open in opposite directionsgenerally in a plane transverse to the axis of rotation of the sprayhead casing 34 about the pedestal 32. The upper interior of the casingarm 37 is further provided with a passageway 41 which extends outwardlyfrom the liquid inlet opening 35. The passageway 41 is divided into aninlet portion 42 connected to the casing liquid inlet opening 35 and twooutlet portions 43 and 44 which have a common intersection 45 with thepassageway inlet portion 42 and extend from opposite sides thereof to arespective one of the propelling orifices 39 and 40'. With thisarrangement, the pressurized wash fluid can be conducted outwardly alongthe passageway 41 to issue from either of the two propelling oriiices 39or 40. As viewed from the top of the dishwasher, issuance of thepressurized wash uid from the propelling orilice 39 will urge the sprayhead casing 34 to rotate in a clockwise direction about the pedestal 32,while issuance of the pressurized wash uid from the other propellingorifice 40 will urge the spray head casing 34 to rotate in a reverse orcounterclockwise direction about the pedestal axis 32.

As shown in FIGURES 3 and 4, the bottom of the hollow casing arm 37 isalso provided with a pair of transversely-spaced aligned control uidinlet ports 46 and 47 which are connected to the passageway 41 byseparate conduits 48 and 49 (partially shown in dotted lines in FIG- URE2). While various control fluids may be used, air is preferably employedin accordance with the presently preferred embodiment.

Each of the airconduits 48 and 49 has a similar crosssectional area thatis considerably smaller 'than those of the liquid passageway portions42-44. The outlet sections 48a and 49a of the air conduits 48 and 49 areconnected to the opposite sides of the liquid passageway inlet portion42 at a point adjacent the intersection 45, opening directly across fromone another and disposed substantially perpendicular to the long axis ofthe inlet portion 42. A substantially circular valve plate 50 isrotatably mounted on the bottom of the casing arm 37 adjacent the ports46 and 47. The Valve plate 50 extends over the ports 46 and 47 in aduid-sealing relationship and is provided with an aperture 51 somewhatlarger than those ports which may be selectively aligned over either ofthe .ports 46 and 47 to open the same by 180 rotation of the valve plate50.

With this arrangement, the pressurized wash iluid in the passageway 41may be selectively directed toward one and away from the other of thepropelling orifices 39 and 40 by rotation of the valve plate 50. Uponrotation of the valve plate 50 to a position opening the port 46,airwill be aspirated through its conduit 48 to the liquid passagewayinlet portion 42 adjacent the intersection 45 and will directpressurized fluid toward propelling orice 39 and away from the otherpropelling orice 40. As seen from Vthe top of the dishwater, this willcause the spray head casing 34 to rotate in a clockwise direction. Eventhough the valve plate 50 may subsequently be rotated to close bothports 46 and 47, the pressurized wash fluid in the passageway 41 willcontinue to be directed toward the propelling orifice 39 by theso-called Coanda eifect until the valve plate 50 is rotated to open theother air port 47. When the valve plate 50 is rotated sufficiently toopen the other port 47, air will then be aspirated through that port 47and its conduit 49 into the liquid passageway inlet p0rtion 42 adjacentthe intersection 45 and will shift the iiow of wash fluid to thepropelling orifice 40. As seen from the top of the dishwasher, the sprayhead casing 34 will now be rotated in a counter-clockwise directionabout the pedestal axis 32.

In order to provide for periodic reversal of the rotation of -the sprayhead casing 34, the peripheral edge of the valve plate 50 is providedwith a gear-like intermittent cam surface 52, and an opstanding arm 53is rigidly attached to the wash chamber bottom wall 20 with its upperend aligned for engagement with cam surface 52. With this arrangement,one of the spaced teeth on the valve plate cam surface 52 intermittentlyengages the upstanding arm 53 with each revolution of spray head casing34 about the tently rotated clockwise until the aperture 51 is againaligned over the port 46, and so on.

The particular cam surface 52 shown in FIGURES 2-4, will cause the sprayhead casing 34 to reverse its direction of rotation about the pedestalaxis 32 after three revolutions; the valve plate aperture 51 beingrotated onethird of the 180 between the two ports 46 and 47 with eachrevolution of the casing 34. However, it is evident that such reversalcan be made to occur after a greater or fewer revolutions of the casing34 by altering the conguration of the valve plate cam surface 52. l

As will be evident from the foregoing description, certain aspects ofthe invention are not limited to the particular details of constructionof the example illustrated, and it is contemplated that othervariations, modifications or applications will occur to those skilled inthe art.

What I claim as new and desire to secure by Letters Patent of the UnitedStates is:

1. In an automatic dishwasher, a reversing spray head assembly,comprising:

(a) a hollow casing supported in the dashwasher for rotation about anaxis and having an arm extending outwardly from said axis,

(b) an opening in said casing for admiting liquid under pressure to theinner end of said arm,

(c) a liquid passageway in said arm for conducting said liquid outwardlythrough a pair of orifices which open in opposite directions from saidarm generally in a plane transverse to said axis so that issuance ofsaid liquid from one of said orifices urges rotation of said casingabout said axis in a lirst direction and issuance of said liquid fromthe other of said orices urges rotation of said casing about said axisin a second direction reversed from said first direction,

(d) said liquid passageway including an inlet portion connected to saidopening and.two outlet portions having a common intersection with saidinlet portion and extending from opposite sides thereof to a respectiveone of said orifices,

(e) a pair of control uid inlet ports in said arm connected to saidopposite sides of said inlet portion adjacent said intersection byseparate conduits in said arm which have a considerably smallercross-section than said passageway portions, and (f) control means forselectively opening and closing said control fiuid inlet ports to allowentry of control fluid through only one of said ports at one time andthus direct said liquid toward one and away from the other of saidorifices whereby the direction of rotation of said casing about saidaxis can be reversed. 2. The invention of claim 1, wherein: (a) saidcontrol fluid is air. 3. The invention of claim 2, wherein: (a) saidcontrol means comprises (i) a valve plate rotatably mounted on said armadjacent said ports and having a peripheral cam surface, and (ii) astationary member engageable with said cam surface to rotate said valveplate relative to said ports. 4. The invention of claim 1, wherein: (a)said casing includes at least one additional orice for issuing saidliquid to generate a wash action. 5. The invention of claim 1, wherein:(a) said liquid comprises wash fluid from a sump in the dishwasher.

References Cited ALLEN N. KNowLEs, Primary Examiner.

B. BELKIN, Assistant Examiner.

Us. C1. xn,

4o la7- 81.5, 239-93

